336
Z. RYCHTER
Fig. 2). It is also possible to compress any part of the heart loop (Figs.
27, 28, 30). Such strictly local intervention, without any reaction in the
adjacent tissue, permitted analysis of the relations between the aortic
FIG. 2.
r Scheme of suppression of an aortic arch by means of a silver microclip (after
Rychter, 1957). Al = allantois; dist, prox = distal, proximal limb bud; VCa ca, cr =vena
cardinalis caudalis, cranialis. (Other abbreviations as in Fig. 1.)
arches themselves, between the aortic arches and the heart loop, and
last but not least, the interdependence of the main parts of the heart
loop during the course of chick development.
II. Experimental Morphology of the Aortic Arches
Because the 1st, 2nd and 5th aortic arches are only transitory structures without any bearing on later development of the cardio-aortic
complex, attention has been concentrated on the 3rd, 4th and 6th
Clips
1
2
3
4
5
3 D
3 D 3 S
4D4S
6D6S
3 D 3 S 4 D
3D3S4B
3D3S6D
3;D3S6S
3 D 3 S 4 D 4 S
3r>3 S 6 D 6s
4D4S6D6S
TABLE ] L
Suppressed Aortic Arches
4 D
3 D 4 D
3 D 6 D
4 D 6 D
4 D 4 S 3 D
4 D 4s3s
4 D 4 S 6 D
4 D 4 $ 6 S
3 D 4 D 6 D 3 S
3 D 4 D 6 D 4 S
3 D 4 D 6 D 6 S
3 D 4 D 6 D 3 S 4 S
3 D 4 D 3 S 4 S 6 S
6 D
3S
3s4s
3s6s
4s6s
6 D 6 S 3 D
6D6S3S
6D6S4D
6D6S4S
3 S 4 S 6 S 3 D
3S4S6S4D
3s4s6 S 6 D
3 D 4 D 6 D 3 S 6 S
3 D 6 D 3 S 4 S 6 S
4s
3l>4s
3D6S
4 D 6 S
3 D 4 D 6 D
3s4 fe 6 S
3 D 4 D 6s
3 S 4 S 6 D
3D4D4S6S
3 D 6 D 3 S 4 S
4D6D3S6S
6s
3s4 D
3 S 6 D
4S6D
3 D 6 D 4s
3S6S4D
4 D 6 D 3 S
4 S 6 S 3 D
3S4S4D6D
3S6S3D4D
4S6S3D6D
3D4D6D4S6S
4D6D3S4S6S
Combinations
(27 62)
6
15
20
15
6
The 62 possible combinations eliminating the aortic arches
The numbers indicate the aortic arch or arches and the subscript indicates the side
(D —dextral, S =sinistral).